Active state

Buttons will appear pressed (with a darker background, darker border, and inset shadow) when active. For <button> elements, this is done via :active. For <a> elements, it's done with .active. However, you may use .active on <button>s should you need to replicate the active state progammatically.

Button element

No need to add :active as it's a pseudo-class, but if you need to force the same appearance, go ahead and add .active.